Effect of humidity on the hysteresis of single walled carbon nanotube field-effect transistors

Single walled carbon nanotube field-effect transistors (SWCNT FETs) are attributed as possible building blocks for future molecular electronics. But often these transistors seem to randomly display hysteresis in their transfer characteristics. One reason for this is suggested to be water molecules adsorbed to the surface of the gate dielectric. In this study we investigate the hysteresis of SWCNT FETs at different relative humidities. We find that SWCNT FETs having atomic layer deposited (ALD) HfO2 - TiO2 - HfO2 as a gate dielectric retain their ambient condition hysteresis better in dry N-2 environment than the more commonly used SiO2 gate oxide. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim